Approaches to Correction of Class III Skeletal Malocclusion

Approaches to Correction of Class III Skeletal Malocclusion Combined Orthodontic and Surgical Approach in the Correction of Class III Skeletal Malocclusion Dr. Abdulaziz AlShahrani Astrac While growth modification and camouflage orthodontic treatment offers a limited solution in treating some skeletal Class III malocclusion depending on the age of the patient , Underlying skeletal severity, alignment of the teeth and the vertical facial proportions, a combination of surgical and Orthodontic therapy is the treatment of choice in all severe skeletal Class III malocclusion. In this case report I present a combination of surgical-orthodontic therapy for an adult female patient with skeletal class III malocclusion which resulted in good skeletal, dental and soft tissue relationship, with marked improvement in function and facial esthetics. Keywords: Class III malocclusion, Orthognathic Surgery, surgical orthodontics Introduction Class III malocclusion is considered to be one of the most difficult and complex orthodontic problems to treat. The prevalence of class III malocclusion has been reported to be as low as 3-5% in the Caucasian population, but is higher in the Chinese and Japanese population (4-13%) (Often associated with maxillary retrusion) [i] , [ii] , [iii] . The etiology of class III is complex and multifactorial. However, there is usually a strong genetic contribution. Genetic factor is one of the etiological factors where one third of children with severe Class III had a parent with the same problem and one-sixth had an affected sibling [iv] . Racial tendency may play a role as the blacks have shown higher incidence than white’s [v] .Environmental factors appear to play an adaptiverole in the etiology of Class III malocclusion [vi] .Class III malocclusion can be associated with other factors such as cleft palate [vii] . Individuals with class III malocclusion show combinations of skeletal and dentoalveolar components. Class III malocclusion may occur as a result of protrusive mandible, retrusive maxi lla, combination of both [viii] . While the most commonly found Class III malocclusion (30%) showed a combination of mandibular protrusion and maxillary retrusion, Maxillary retrusion alone was found in 19.5% of the sample and Mandibular protrusion alone was found in 19.1% of the sample [ix] .These complex nature of class III requirea careful planning, amultidisciplinary approach and patient cooperation [x] . Case Report A 17-year-old caucasian girl presented for orthodontic treatment because of referral from her dentist with primary complaint of un-esthetic facial and dental appearance. She has a hyper-divergent Class III skeletal and dental relationship. This is characterized by retrognathic maxilla, retroclined lower anterior teeth, with maximum active opening of 47mm with 5mm negative overjet and lateral excursions of 7 mm to both right and left sides. The patient has an ovoid, relatively asymmetrical face with chin slightly deviated to the left. The lip line at rest displayed a pproximately 2 mm of upper incisor. At full animation there was 7mm of upper incisal display and 2 mm of lower incisal edge. She has a slightly concave profile, and competent lips[Figure1]. Pretreatment extra oral photos Intraorally, the oral mucosa was healthy. There were no periodontal pockets present. The gingival tissues were inflamed especially around the prosthetic crowns. There was no bleeding tendency except sometimes with brushing. Free gingival margins were near to the CEJ and attached gingiva was of normal width throughout the mouth. The frenal attachments in both arches were normal. The tongue was normal in size, function and appearance. Teeth # 26, 36 and 46 have been crowned. There was a lingual arch placed one year ago to maintain lower incisors position.